The present invention relates to a rotary piston machine. More particularly, it relates to a rotary piston machine which has a centrally guided inner gear wheel, and an outer gear wheel whose axis moves circularly about an axis of rotation of the inner gear wheel.
Rotary piston machines of the above-mentioned general type are known in the art. Such machines are disclosed, for example, in the German Offenlegungsschrift No. 1,703,406 and in the German Pat. Nos. 1,528,998 and 1,528,997. These machines, however, are provided with control systems of the conventional rotary piston machines. This means that a displacement unit which is composed of the inner gear wheel and the outer gear wheel, is separated by stationary or movable control plates of a hydraulic distributor. It is, however, possible to drop the control plate and to perform its functions directly by the displacement unit so as to economize the control plate. One approach to solving this problem is disclosed in the German Offenlegungsschrift No. 2,240,632. The construction disclosed in this patent has a planetarily movable rotor which makes impossible the maintaining of an adequate cross-section for passing of a sufficient quantity of working medium so as to obtain a sufficient number of revolutions of the machine. Moreover, additional auxiliary plates and cover plates for controlling the fluid and complicated control openings in the rotor and the plates are required in this construction.